The broad, long-term objective of the current research (responding to RFA-DA-15-010) is to reduce the prevalence of prescription stimulant medication (PSM) misuse among college students, through development and testing of efficacious and cost-effective personalized feedback interventions (PFI) targeting college students' perceived benefits of PSM, normative perceptions of PSM, and increasing alternative behaviors, thereby reducing PSM and other substance use (specifically marijuana and alcohol). Up to 36% of college students have engaged in PSM misuse and this is linked with increased consequences, including health consequences, reduced GPAs and class attendance, and comorbid use of other substances. Research indicates several key reasons students turn to PSM such as to increase academic performance and energy and regulate the effects of other drugs. However no interventions have been tested for PSM misuse among college students. This application is a collaboration of 3 research teams with unique strengths to address this problem. Dr. Arria's College Life Study (CLS) is one of the largest and most comprehensive studies of PSM in college students to date. The University of Washington (Geisner, Kilmer, Lee, Larimer) are pioneers in developing and adapting screening and brief web- and in-person Personalized Feedback Interventions (PFI) for a range of addictive behaviors. The University at Albany (Cimini) is nationally recognized for implementing cutting edge assessment and interventions into real-world campus health and counseling settings. The current research builds on our prior work on risk factors, consequences, motives, norms perceptions and benefits of PSM and development of PFI approaches for alcohol, marijuana, and other drug use. Research indicates brief, web-based and in-person PFI targeting a wide variety of substances and conditions, including accurate norms feedback, beliefs and perceptions feedback, and alternative strategies, are efficacious in reducing symptoms, correcting norms, and reducing substance use in a vulnerable population (college students). The current study extends this work by developing and testing an innovative PFI developed specifically to target student PSM misuse. Specific aims are: 1) Establish norms of PSM for use in the PFI and solicit feedback on intervention components; 2) Develop and test efficacy of a web-based PFI to reduce PSM misuse, as well as alcohol and marijuana use, among college students at 6, 12, and 18 month follow-ups. Evaluate normative perceptions, PSM-related beliefs, and alternative behaviors as mediators of intervention efficacy as well as motives for use and demographic variables as moderators; and 3) Compare efficacy, mediators, and moderators of the web- based PFI versus an in-person MI-based PFI versus control in reducing use and consequences of PSM, alcohol and marijuana among students seeking services at Counseling and Health Centers.